1. Field of the Invention
The present invention relates to a sheet feeding apparatus and an image forming apparatus, and in particular, relates to a sheet feeding apparatus having a sheet cassette in which sheets are stacked and an image forming apparatus having the sheet feeding apparatus.
2. Description of the Related Art
Conventionally, an image forming apparatus such as a copying machine and a printer is structured to include a sheet feeding portion to feed a sheet to an image forming portion. Such a sheet feeding portion includes a plurality of sheet cassettes in which various sizes of sheets are stored.
As disclosed in Japanese Patent Laid-Open No. 2008-50081, such a plurality of sheet cassettes respectively includes a guided member as being slidable against a guide member arranged at an apparatus body. Then, sliding movement of the sheet cassettes to the apparatus body is smoothed by arranging a sliding member at the guided member, so that sheet cassette operability for attaching and detaching is improved.
Here, FIG. 14 illustrates a state that the sheet cassette is to be attached to a feeding apparatus body according to Japanese Patent Laid-Open No. 2008-50081. In a case that a sheet cassette 100 is rotated in a direction of arrow Y during attaching and detaching, there is a fear that the sheet cassette 100 is damaged as being contacted to an external cover and a structural member located therearound. Accordingly, as illustrated in FIG. 14, in the sheet feeding apparatus disclosed in Japanese Patent Laid-Open No. 2008-50081, the rotation of the sheet cassette 100 in the direction of arrow Y during attaching and detaching is limited into an established angle by arranging side rollers 102 at lateral ends of an inner rail 101 in the horizontal direction. Further, at the inside of the apparatus body 110, positioning rollers 112 are arranged at both end sides of an outer rail 111 in the horizontal direction. Positioning of the sheet cassette 100 inside the apparatus body 110 is performed by the positioning rollers 112.
Here, in the light of positional variation of the positioning rollers 112 arranged at the apparatus body 110, sliding resistance is generated for performing positioning of the sheet cassette 100 when a clearance between the side roller 102 and the outer rail 111 is lessened. In particular, a large volumetric sheet cassette causes large sliding resistance as a result of large dimensions of structural members. When the sliding resistance becomes large, operational force required for attaching and detaching the sheet cassette becomes large. Accordingly, there is a fear that operability thereof is decreased.
The present invention provides a sheet feeding apparatus capable of reliably restricting movement of a sheet cassette in the horizontal direction without decreasing operability of the sheet cassette and an image forming apparatus having the sheet feeding apparatus.